自己些的用COM实现MFC单文档程序的多个视图，视图以COM插件的方式动态添加到MFC主程序，添加一个视图后将在工具栏上出现一个按钮。-More use of their own MFC Single Document COM implementation process multiple views, view to the way COM plug-ins added to the MFC dynamic main program, add a view on the toolbar wil